[C320-list] battery/charger issue

[Jeff Hare]

Hey Chris,

Few questions about your setup might help also:

- Were you on a doc plugged in when you first noticed the smell but before
you went over for a pumpout?
- Do you have the standard yanmar/hitachi alternator or do you have an
upgraded alternator and external regulator?
- Are your house batteries wired in Parallel or did you have the switch set
to just the one that died?
- Any chance that the air and water temp was warmer where you are than it
had been in the previous few weeks?

In any event, You're most likely the victim of thermal runaway.  The thermal
runaway safety zone limits decrease with age and are more likely to suffer
from this even if the batteries appear to be in good condition and have good
holding capacity.  A warmer than normal battery compartment can allow this
to happen sooner, especially since our battery compartments are "insulated"
on top.  Chargers that don’t have a battery temp sensor can't know to reduce
the float or charge voltage as the battery heats up.  Engine alternator
normally produces 13.8v which is higher than a shore power charger's normal
float voltage of around 13.2 or so.

People like to fully blame the ProMariner, but I'd put money down that it's
usually some combination of battery age, ambient temp in the battery
compartment and the charger's lack of thermal sensor that sets up for this
cascade. A problem battery will fry at float voltage in the right ambient
conditions regardless of who supplies the float voltage and you're unlikely
to have any warning.

I'm guessing that your battery had a defect that made it susceptible to this
earlier in its life than it should have.

-Jeff

-----Original Message-----
From: c320-list-bounces at lists.catalina320.com
[mailto:c320-list-bounces at lists.catalina320.com] On Behalf Of Karl
Mielenhausen
Sent: Monday, May 14, 2012 7:17 PM
To: C320-List at catalina320.com
Subject: Re: [C320-list] battery/charger issue

You're right Chris... that is a different animal altogether.
Most likely a bad cell in the battery. Alternator keeps trying to charge and
results in overcharge of good cells.
See if one cell still has normal electrolyte level. If so, that is the bad
one and it is time for a new battery.
You could also use a battery hydrometer to measure the specific gravity in
each cell. Differences greater than .02 indicate a problem.


Karl

On Mon, May 14, 2012 at 6:00 PM, Chris Descher <cdescher at cedtulsa.com>
wrote:
> Something that I still don't understand is that the battery was 
> boiling and overheating while we were motoring.  The circuit breaker 
> to the charger was turned off.  How would it be the charger?
>
> -----Original Message-----
> From: c320-list-bounces at lists.catalina320.com
> [mailto:c320-list-bounces at lists.catalina320.com] On Behalf Of 
> hcreech at comcast.net
> Sent: Monday, May 14, 2012 9:46 AM
> To: C320-List at Catalina320.com
> Subject: Re: [C320-list] battery/charger issue
>
>
> Chris,
> If your charger is a ProMariner that is definitely the problem. this 
> has been reported many times here. I originally had a ProMariner on my 
> 99' boat, it was noisy and fried batteries without notice. Switch it 
> for a Xantrex and never had another problem, you can't hear a thing.
>
> Herb Creech
> Cloud Chaser 606
>
>
>
>
> ----- Original Message -----
> From: "Chris Descher" <cdescher at cedtulsa.com>
> To: C320-List at Catalina320.com
> Sent: Monday, May 14, 2012 8:55:21 AM
> Subject: [C320-list] battery/charger issue
>
> This weekend I noticed a bad smell in the boat and thought that it 
> might be the head. I got a pumpout, but the smell remained. Motoring 
> back to the dock I started going through the cabin searching for the 
> source. It turned out to be the 4D house battery. The acid was boiling 
> out, and it took more than an hour for it to cool down enough that I 
> could disconnect and remove it. This battery is less than two years 
> old, and I've always maintained the liquid level. The boat is a 1998 
> model, and I still have the original charger. Any guesses as to 
> whether this was a battery problem or a charger problem? The starting
battery seems to be fine.
>
> Chris Descher
> #500
>